SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '78e549d8969dcc6759c123a4992299f07f79139793ff8db3f825e714f81ef826' 
  AND token = 'P6KE/isAnzZ1kKiU/+UQ8+AvD/uZElgqQq8baaiNp20=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}